Is CVE-2026-42977 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-42977 being exploited in the wild.

How severe is CVE-2026-42977?

High severity, with a CVSS score of 7.8, published 9 June 2026.

Is there a fix for CVE-2026-42977?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-42977 attacked?

It is attacked with local access, in an operating system.

Am I affected by CVE-2026-42977?

Check whether you run Microsoft Windows Push Notifications. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-42977: Microsoft Windows Push Notifications race condition privilege escalation

CVE-2026-42977 · Severity: high · CVSS 7.8 · Published 2026-06-09

A security vulnerability exists in the Windows Push Notification service, which handles the delivery of real-time alerts and updates to applications. An attacker who already has limited access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to view sensitive data, install malicious software, or disrupt business operations.

Technologies: Microsoft Windows Push Notifications. Vendors: Microsoft.

Quick answers

Is CVE-2026-42977 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-42977 being exploited in the wild.
How severe is CVE-2026-42977?: High severity, with a CVSS score of 7.8, published 9 June 2026.
Which products and versions are affected?: Microsoft Windows Push Notifications.
Is there a fix for CVE-2026-42977?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-42977 attacked?: It is attacked with local access, in an operating system.
Am I affected by CVE-2026-42977?: Check whether you run Microsoft Windows Push Notifications. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A race condition (CWE-362) exists in the Windows Push Notifications service due to improper synchronization when accessing shared resources. To exploit this, an attacker must first have local access to the system with low-level privileges. By successfully winning the race condition during concurrent execution, the attacker can achieve a privilege escalation, potentially gaining SYSTEM-level access. The vulnerability is characterized by high complexity (AC:H) and requires local authentication (PR:L), but it allows for a full compromise of confidentiality, integrity, and availability.

Affected products

Microsoft Windows Push Notifications

Timeline

2026-06-09: disclosed
2026-06-09: advisory

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42977

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